Centre for Environmental Management, CQ University, Rockhampton, Queensland, Australia.
Environ Toxicol. 2011 Jun;26(3):260-70. doi: 10.1002/tox.20552.
The presence of a toxic strain of a fine filamentous cyanobacterium belonging to the Oscillatorialean family Pseudanabaenacea was detected during a survey of cyanobacterial taxa associated with the presence of cylindrospermopsin in dams in Central Queensland (Australia). The strain, AC0243, was isolated and cultured, its genomic DNA extracted and 16S RNA gene sequenced. Phylogenetic analysis placed AC0243 with Limnothrix species, although this genus appears polyphyletic. Moreover, not all morphological characters are consistent with this genus but more closely fit the description of Geitlerinema unigranulatum (R.N. Singh) Komárek and Azevedo. The potential toxic effects of AC0243 extract were assessed chemically and biologically. Cell free protein synthesis was inhibited by the extract. Exposure of Vero cells to the extract resulted in a significant reduction in cellular ATP levels following 24-72 h incubation. The presence of cylindrospermopsin was excluded based on the nature of responses obtained in cell and cell-free assays; in addition, (i) it could not be detected by HPLC, LC-MS, or immunological assay, and (ii) no genes currently associated with the production of cylindrospermopsin were found in the genome. Other known cyanobacterial toxins were not detected. The apparent novelty of this toxin is discussed.
在对澳大利亚昆士兰州中部水坝中与圆柱鱼腥藻素存在相关的蓝藻分类群进行调查时，发现了一种属于 Oscillatorialean 家族 Pseudanabaenacea 的有毒细丝状蓝藻的存在。该菌株 AC0243 被分离和培养，提取其基因组 DNA 并测序 16S RNA 基因。系统发育分析将 AC0243 与 Limnothrix 种放在一起，尽管这个属似乎是多系的。此外，并非所有形态特征都与该属一致，但更符合 Geitlerinema unigranulatum (R.N. Singh) Komárek 和 Azevedo 的描述。评估了 AC0243 提取物的潜在毒性作用。无细胞蛋白质合成被提取物抑制。暴露于提取物的 Vero 细胞在孵育 24-72 小时后细胞内 ATP 水平显著降低。基于细胞和无细胞测定中获得的反应性质排除了圆柱鱼腥藻素的存在；此外，(i) 它不能通过 HPLC、LC-MS 或免疫学测定检测到，并且 (ii) 在基因组中未发现与圆柱鱼腥藻素生产相关的基因。未检测到其他已知的蓝藻毒素。讨论了这种毒素的明显新颖性。
